This apparatus is intended for use with the type sewage treatment unit shown and described in U.S. application Ser. No. 082,964, filed Oct. 9, 1979, now U.S. Pat. No. 4,253,957, which may have both marine and land base applications.
Of particular interest are the disclosures which deal with sewage treatment apparatus having sludge return lines. The following are relevant U.S. Pat. Nos.:
2,901,114 Smith et al PA1 3,487,937 Koulovatos PA1 3,722,836 Savage et al PA1 3,767,051 Thompson PA1 3,884,815 Cornelissen PA1 3,992,299 Wray. PA1 3,342,727 Bringle PA1 3,355,019 Mitchel PA1 3,382,981 Hampton PA1 3,522,881 Nicol PA1 3,721,344 Rost PA1 3,807,563 Reid Jr.
Also background art includes the following U.S. Pat. Nos.: